Instead of hardcoding value for the maximum discard sector to UINT_MAX >> 9, allow user to set the value with newly added module parameter max_discard_sectors. To retain the backward compatibility make set default value to UINT_MAX >> 9. Signed-off-by: Chaitanya Kulkarni <kch@xxxxxxxxxx> --- drivers/block/null_blk/main.c | 10 +++++++++- drivers/block/null_blk/null_blk.h | 1 + 2 files changed, 10 insertions(+), 1 deletion(-) diff --git a/drivers/block/null_blk/main.c b/drivers/block/null_blk/main.c index 96b8aca5abda..2f787807cf63 100644 --- a/drivers/block/null_blk/main.c +++ b/drivers/block/null_blk/main.c @@ -216,6 +216,10 @@ static bool g_discard; module_param_named(discard, g_discard, bool, 0444); MODULE_PARM_DESC(discard, "Support discard operations (requires memory-backed null_blk device). Default: false"); +static unsigned int g_max_discard_sectors = UINT_MAX >> 9; +module_param_named(max_discard_sectors, g_max_discard_sectors, uint, 0444); +MODULE_PARM_DESC(max_discard_sectors, "Maximum size of a REQ_OP_DISCARD command (in 512B sectors)."); + static bool g_write_zeroes; module_param_named(write_zeroes, g_write_zeroes, bool, 0444); MODULE_PARM_DESC(write_zeroes, "Support write-zeores operations. Default: false"); @@ -420,6 +424,7 @@ NULLB_DEVICE_ATTR(home_node, uint, NULL); NULLB_DEVICE_ATTR(queue_mode, uint, NULL); NULLB_DEVICE_ATTR(blocksize, uint, NULL); NULLB_DEVICE_ATTR(max_sectors, uint, NULL); +NULLB_DEVICE_ATTR(max_discard_sectors, uint, NULL); NULLB_DEVICE_ATTR(irqmode, uint, NULL); NULLB_DEVICE_ATTR(hw_queue_depth, uint, NULL); NULLB_DEVICE_ATTR(index, uint, NULL); @@ -544,6 +549,7 @@ static struct configfs_attribute *nullb_device_attrs[] = { &nullb_device_attr_queue_mode, &nullb_device_attr_blocksize, &nullb_device_attr_max_sectors, + &nullb_device_attr_max_discard_sectors, &nullb_device_attr_irqmode, &nullb_device_attr_hw_queue_depth, &nullb_device_attr_index, @@ -686,6 +692,7 @@ static struct nullb_device *null_alloc_dev(void) dev->queue_mode = g_queue_mode; dev->blocksize = g_bs; dev->max_sectors = g_max_sectors; + dev->max_discard_sectors = g_max_discard_sectors; dev->irqmode = g_irqmode; dev->hw_queue_depth = g_hw_queue_depth; dev->blocking = g_blocking; @@ -1850,7 +1857,8 @@ static void null_config_discard(struct nullb *nullb) } nullb->q->limits.discard_granularity = nullb->dev->blocksize; - blk_queue_max_discard_sectors(nullb->q, UINT_MAX >> 9); + blk_queue_max_discard_sectors(nullb->q, + nullb->dev->max_discard_sectors); } static void null_config_write_zeroes(struct nullb *nullb) diff --git a/drivers/block/null_blk/null_blk.h b/drivers/block/null_blk/null_blk.h index 2c0c9c29158f..09940211326d 100644 --- a/drivers/block/null_blk/null_blk.h +++ b/drivers/block/null_blk/null_blk.h @@ -102,6 +102,7 @@ struct nullb_device { unsigned int queue_mode; /* block interface */ unsigned int blocksize; /* block size */ unsigned int max_sectors; /* Max sectors per command */ + unsigned int max_discard_sectors; /* Max discard sectors per command */ unsigned int irqmode; /* IRQ completion handler */ unsigned int hw_queue_depth; /* queue depth */ unsigned int index; /* index of the disk, only valid with a disk */ -- 2.29.0